Presentation on theme: "A Case History of Hypertension in Pregnancy"— Presentation transcript:
1 A Case History of Hypertension in Pregnancy Max Brinsmead MB BS PhDApril 2014
2 Carol is a 36-year old Intensive Care Nurse who has been trying to have a baby for 5 years. She conceives spontaneously and commences antenatal care in Sydney. During a “weekend away” in Coffs Harbour she comes to Maternity feeling a little unwell and asks to have her BP checked. It is 160/105. The midwife starts a CTG and asks that you come to see this patient.
3 Carol is pregnant with a BP of 160/105 Is this preeclampsia or pregnancy-induced hypertensionHow urgent is this reviewWhat further history do you requirePreeclampsia is sustained hypertension in the 2nd half of pregnancy accompanied by evidence of some other organ involvement. Returns to normal after 3mNot urgent, but symptoms are worrying…This pregnancy. Other pregnancies. Personal and Family medical history. Social circumstances. Symptoms.
4 Carol with a BP of 160/105Gestation is 33 weeks by dates and early scansNever pregnant before.All tests thus far, including PAPP-A for triploidy, are normal.Had “nephritis” aged 6 years but recovered after 6 weeks.Mother is hypertensive on medicationMarried to another nurse. Non smoker. Usually fit and healthy but just “feels unwell and thought her BP might be up”.BP in the first trimester was 105–115/60–75 and was 130/80 one week ago.
5 Carol G1P0 at 33 weeks with a BP of 160/105 What further information do you requireWhat tests are desirableWould you admit this patient to the antenatal ward?Repeat BP after resting. Cardiovascular and pregnancy examination. Test urine for proteinFBC, UEC, LFTs, Urate, Proteinuria quantification, UMCSPregnancy ultrasoundYES
6 Carol G1P0 at 33 weeks BP 160/105Cardiovascular exam is normal apart from accentuated 2nd heart sound. Mild generalized oedema noted.Symphysis-fundal height 29 cmKnee jerks are active but there is no sustained clonusOedema is no longer regarded as a sign of preeclampsiaBecause oedema is a “good sign” in pregnancyThis uterus is small for datesIt is normal to have 1-2 beats of clonus but sustained clonus is a sign of imminent eclampsia
8 Ward test proteinuria + HB 128 Hct 0.36 Platelets 231 Carol G1P0 at 33 weeks BP 160/105Ward test proteinuria +HB 128 Hct 0.36 Platelets 231UEC and LFT’s normal. S Creat normal. Urate 0.3824-hr urine protein 0.25G (normal <0.3G)UMCS – no red/white cells or casts. Culture negativeEstimated Fetal Weight (EFW) by ultrasound <10th centile with evidence of head-sparing IUGR. Reduced amniotic fluid index. Umbilical UA Dopplers 95th centile
9 Estimated Fetal Weight by Ultrasound Is made by ultrasonic measurements of head biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and Femur Length (FL)Has an error of not less than ± 20%Fetal growth restriction is either generalised (symmetrical) or head-sparing (asymmetrical)Asymmetrical IUGR arises from a redirection of cardiac output to support vital brain growth
10 Is largely composed of fetal urine Amniotic FluidIs largely composed of fetal urineIt’s volume is a reflection of fetal urine outputWhich, in turn, is a reflection of fetal cardiac output/function, fetal oxygenation and welfareWill be absent if there is renal agenesis or urine output obstructionIs often expressed as the Amniotic Fluid Index (AFI)
11 Umbilical Artery Doppler Study Upper panel represents peak (systolic) and trough (diastolic) flow often expressed as S/D ratioLower panel is constant flow through a uterine veinUA Doppler reflects downstream placental resistanceIs the 1st change to occur with placental disease
12 Umbilical Artery Doppler changes with Gestation
13 Abnormal UA Doppler Flows When flow ceases in the diastolic phase (AEDF) the S/D ratio is very high (∞)Flow may even reverse in the diastolic phase (RDF) as shown opposite
14 Why is that an important diagnosis Carol G1P0 33 weeks BP of 160/105 but no significant proteinuria. Clinical and scan evidence of IUGRIs this preeclampsiaWhy is that an important diagnosisYESPreeclampsia is an unpredictable disease with significant maternal and fetal mortality and morbidity
15 Systems involved in Preeclampsia RenalSignificant proteinuriaRenal failure biochemistryOliguriaHepaticElevated transaminasesEpigastric or RUQ painHaematologicalThrombocytopeniaHaemolysisDICCNSEclampsia or strokeHyperreflexia with sustained clonusSevere headache or visual disturbanceCardiovascularPulmonary oedemaPlacentalIUGRAbruption
16 Carol 33 weeks with preeclampsia in hospital Carol 33 weeks with preeclampsia in hospital. BP rises to 180/110 at 6 pm with dull headache. No sustained clonusDoes this hypertension require treatmentWhyWhat drug will you useWhat BP would you aim to achieveYesRisk of eclampsia, cerebral haemorrhage and pulmonary oedemaAldomet or Labetalol with a loading doseReduce BP to / so as not to further compromise uterine blood flow
17 Carol 33 weeks with preeclampsia Carol 33 weeks with preeclampsia. Over the next 2 days her BP continues to rise, especially at nightWhat measures can you use to control the BPHow will you monitor fetal wellbeing on a daily basisUse drugs to maximum possible doses. Then add in other drugs from a different classFor example, Aldomet + Labetalol + Nifedipine + PrazosinFetal movement charts and non stress cardiotocography (CTG)
18 Antenatal (Non stress) CTG 10–40 min of continuous FHRTocograph for fetal movements + maternal triggerIs an assessment of fetal CNS and cardiac oxygenationHigh negative predictive value when “reactive"
19 Carol now 34 weeks. BP difficult to control Carol now 34 weeks. BP difficult to control. She develops severe epigastric pain and vomiting.Deteriorating preeclampsia with a significant risk of fitsAcute liver swelling stretches its capsule. Maybe subcapsular haematomaAST 240, ALT 115 (NR <70)What is the most likely diagnosisWhat causes the painWhat tests may be useful
20 A course of steroids to promote fetal lung maturation Carol 34 weeks with uncontrolled hypertension and epigastric pain. Ultrasound shows no further fetal growth and AEDF with Doppler of the umbilical arteries.DELIVERYA course of steroids to promote fetal lung maturationHow will you CURE this patientWhat steps may be desirable on behalf of the baby
21 How can you deliver this patient Carol 34 weeks with severe preeclampsia and fetal compromise requires deliveryInduction of labour best for mother but baby may not tolerate the hypoxic stress of contractions. Cervix may be unfavourable.Caesarean quick and best for baby but riskier for mother and may compromise her future deliveriesHow can you deliver this patientDescribe the pros and cons of each method
22 First aid is more important than drugs As preparations are being made for a Caesarean Carol has a grand mal seizure. You are present as it commences…First aid is more important than drugsProtect from injurySecure an airwayAdminister oxygenThen secure IV accessIV MgSO4 loading dose and maintain by infusionWhat do you do
23 IV Hydrallazine or Diazoxide used most in Australian practice Carol 34 weeks has had an eclamptic fit. MgSO4 continues by infusion. Her BP is 180/120.IV Hydrallazine or Diazoxide used most in Australian practiceRisk of respiratory and cardiac arrest. Monitor urine output, respirations, O2 saturation, knee jerks and serum Mg levelsWhat drugs are useful now to lower BPWhat are the risks from the MgSO4 and how is that avoided
24 Not less than 24 hours after delivery Carol undergoes urgent Caesarean section and is transferred to Intensive Care for postoperative careNot less than 24 hours after deliverySeparation of mother and infant interferes with bonding and lactation.Insomnia and stress to Carol and her relatives.May increase the risk of thromboembolismHow long should the MgSO4 infusion continueWhat are the problems that may arise from intensive care
25 The baby weighs 1800g and has signs of IUGR. Hypoglycaemia due to depleted glycogen liver storesMonitor blood glucose levels. Early feeding by suckling or D-tube or IV glucose may be requiredWhat is the most common neonatal problem for this babyHow is it avoided
26 The baby does well. Carol’s BP still requires treatment postpartum. 24-72 hours but renal/hepatic function may get worse before it gets betterKeep BP <150/100, drugs may be required for 6-12 weeksAny antihypertensive drug can be used (but some patients don’t respond to ACE inhibitors)When would expect recovery of renal or hepatic dysfunctionHow about the hypertensionWhat drugs are used in the control of hypertension
27 Carol’s BP is normal off all medication by 6 weeks Carol’s BP is normal off all medication by 6 weeks. Tests for autoimmune disease and thrombophilia are negative50 – 66%Low dose aspirin (100 mg daily preferably commencing in the 1st trimester) reduces risk by >17%Also use Ca supplements 1.5G/dayYESWhat is the risk that she will develop preeclampsia in a subsequent pregnancyHow could that risk be reducedIs Carol at risk of hypertension in the future